It will be appreciated that, in railroad and/or mass and rapid transit operations, it is necessary to determine when an electropneumatic dump valve, such as, a type N-7-D magnet valve, has failed since the failure may result in the inability to release the brakes during a wheel slip condition. Normally, the dump valve is pneumatically interposed between the brake cylinder and a suitable source of fluid pressure, such as, a pneumatic brake control valve, so that during braking of the railway vehicle, the brake cylinder is pressurized to cause application of the brakes. Now when a wheel slip condition occurs, it is desirable to deactivate or release the brakes by electrically energizing the coil portion of the dump valve so that the valve portion is mechanically shifted to a position which blocks off the pressure from the pneumatic brake control valve and exhausts the brake cylinder to atmosphere. In some situations, a faulty dump valve may inhibit the actuation of the wheel slip control. That is, if the coil portion fails due to a short or open circuit, the solenoid plunger cannot functionally cause a common port to be connected to one or the other ports. Similarly, a mechanical failure results in the inability of connecting the common port with one or the other ports. Thus, it is highly advantageous to monitor the integrity of the dump valve to ascertain the electrical state, as well as the mechanical condition in order to forewarn and alert an end user of a possible approaching problem which could result in damage to the equipment and lading.